EV Battery Degradation: What the Geotab Data Can Tell You

Fluxtrio editorial team · Prepared and reviewed 16 October 2026

Summary

Geotab's updated analysis reports average annual battery degradation of 2.3%, using data from more than 22,700 EVs across 21 models. It also finds substantial differences between operating groups. The average describes the analysed fleet; it is not a diagnosis of a used car or a guaranteed annual loss for every battery. G

Compare battery-health scenarios in Fluxtrio. Use a measured state of health where available, then keep speed, temperature and charge window fixed when comparing capacity assumptions. F

What is battery degradation?

It is a gradual reduction in the battery's ability to store energy. Geotab measures battery state of health, or SoH, as current usable capacity relative to capacity when new. State of charge, or SOC, describes the current charge level instead. A battery can be fully charged relative to its present capacity while retaining less energy than when new. G

That distinction matters when interpreting a dashboard. Recurrent describes winter range reduction as seasonal and reversible as temperatures recover; Geotab studies longer-term capacity change. A cold-weather range estimate therefore cannot establish the car's SoH by itself. R

Our recommendation for a used-car comparison is to ask for the method and date behind the health figure, then consider the actual vehicle's condition alongside the broader research. A fleet average is useful context, but it cannot substitute for information about that car.

What does Geotab's average mean?

The opened article presents a 2025 analysis, in a page dated 28 April 2026. It reports the average above and explicitly warns that individual vehicles can differ because of intrinsic battery properties and usage. It also notes that the composition of successive datasets affects their averages. G

Comparing those headline averages as if the same battery population had suddenly changed performance would miss that explanation. Geotab discusses charging practices, vehicle mix and a greater share of newer vehicles as possible contributors to the result. Those interpretations belong to the study, rather than being demonstrated causes for any individual battery. G

The article includes longer-term projections. This guide does not use them as a promise that an individual car will retain a particular capacity at a future age. Extrapolating an average would add assumptions about the shape and persistence of degradation. Geotab itself discusses early capacity decline followed by a change in rate for many EVs. G

What did the charging groups show?

Geotab reports annual degradation up to 3.0% for heavy high-power DC charging versus 1.5% in the low-power group. This is an association in observational cohorts, not proof of the effect of one charging stop or a diagnosis of an individual battery. G

What about climate and charge level?

Geotab reports faster average degradation in its hot-climate group and says its dataset lacked sufficient consistently cold-only samples to isolate the long-term effect of extreme cold. It would therefore be misleading to turn a winter driving-range loss into a quantified claim about permanent cold-weather damage from this study. G

Its SOC analysis examines time spent at high or low charge levels, across driving, charging and rest. That is a different exposure from occasionally reaching a charging limit before departure. The study's thresholds describe its grouped data; they do not replace the manufacturer-specific charge guidance for a particular battery chemistry. G

For seasonal driving effects, read winter range. For a cold fast-charging stop, see preconditioning.

How does SoH affect a range calculation?

Fluxtrio multiplies usable capacity by SoH and the selected SOC window before dividing that energy by consumption. For examples using actual catalogue capacities and model output, see the used-EV battery guide. Capacity retention and seasonal consumption are separate inputs. M

What should a used-EV buyer ask for?

We recommend asking for a recent health report, its measurement method, the applicable battery warranty terms and any relevant repair history. Treat an unexplained percentage as a prompt for questions rather than a complete inspection.

Geotab describes estimating capacity through energy transfers and changes in SOC over time. That is more specific than merely converting a dashboard distance prediction into a health percentage. Its aggregate findings also leave room for differences between individual vehicles. G

Use the candidate car's measured health in a scenario matching your route. Then change temperature and speed separately to see whether the winter journey still looks practical. For the energy-cost consequence of different consumption assumptions, read charging costs.

Methodology and limits

This article uses the opened Geotab primary report and preserves its grouping definitions. It does not infer battery replacement rates, assert a universal lifespan or extrapolate linear degradation into a warranty claim. The SoH calculation is explicitly illustrative. Seasonal range information comes from Recurrent and is kept separate from permanent capacity change. G

Compare measured battery health in Fluxtrio, keeping the route conditions and charge window unchanged.

FAQ

How much capacity do EV batteries lose each year?

Geotab reports a 2.3% annual average for its analysed fleet. Individual vehicles and operational groups differ, so this is not a universal annual deduction. G

Is SoH the same as the charge percentage?

No. SoH describes retained capacity relative to new, while SOC describes the current charge level. G

Does a low winter range estimate prove degradation?

No. Recurrent describes a temporary seasonal effect; assessing capacity requires a separate battery-health measurement. R

Does one fast-charging session imply a specific amount of damage?

No. Geotab's findings compare operational groups over time and do not quantify damage from an individual charging stop. G

Sources

• G Geotab, How long do electric car batteries last? The updated guide to real-world EV battery health, 28 April 2026; sample, charging groups, SOC, climate, data limits and health-measurement FAQ. Accessed 16 October 2026.
• R Recurrent, Best EV for Winter & Cold Weather Range, 19 November 2025; temporary winter effect. Accessed 16 October 2026.
• F Fluxtrio, calculator and usable-energy explanation. Accessed 16 October 2026.
• M Fluxtrio, Metodika odhadu dojezdu (Czech); usable energy and model limitations. Accessed 16 October 2026.